When operating in an infrastructure mode, wireless local area networks (WLANs) typically include an access point (ΔP) and one or more client stations. WLANs have evolved rapidly over the past decade. Development of WLAN standards such as the Institute for Electrical and Electronics Engineers (IEEE) 802.11a, 802.11b, 802.11g, and 802.11n Standards has improved single-user peak data throughput. For example, the IEEE 802.11b Standard specifies a single-user peak throughput of 11 megabits per second (Mbps), the IEEE 802.11a and 802.11g Standards specify a single-user peak throughput of 54 Mbps, the IEEE 802.11n Standard specifies a single-user peak throughput of 600 Mbps, and the IEEE 802.11ac Standard specifies a single-user peak throughput in the Gbps range. Work has begun on a new standard, IEEE 802.11ax, which will provide even greater throughput.
IEEE 802.11af specifies wireless network operation in sub-1 GHz frequencies. Low frequency communication channels are generally characterized by better propagation qualities and extended propagation ranges compared to higher frequency communication channels. In the past, sub-1 GHz frequency ranges have not been utilized for wireless communication networks because such frequencies were reserved for other applications (e.g., licensed TV frequency bands, radio frequency band, etc.). There are few frequency bands in the sub-1 GHz range that remain unlicensed, with different unlicensed frequencies in different geographical regions. The IEEE 802.11af Standard specifies wireless operation in TV White Space (TVWS), i.e., unused TV channels in sub-1 GHz frequency bands.
Work has begun on another new standard, IEEE 802.11ah, which will specify wireless network operation in sub-1 GHz frequencies. The IEEE 802.11ah Standard will specify wireless operation in available unlicensed sub-1 GHz frequency bands.